Instruction Manual

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solutions that have not been used for a long time, slowly flip the vial twice and let it stand for
2 minutes. Be careful not to shake the solution vigorously, as this will create air bubbles
which will destabilize the measurement; For 0.0 NTU calibration solution, do NOT shake or
flip. If using Formazin calibration solution, as it tends to precipitate easily, each time users
must flip and shake the vial to make the solution even. But sediment can still occur during
tests and would make the measurement unstable. Users need to have rich experience
handling Formazin calibration solutions.
4.2 Calibration Procedure (Take 0 NTU and 20 NTU as an example)
1) Instrument warm up (only required for low-range or high-accuracy measurement):
Power on the instrument, set parameter P2 (continuous measurement time) to 5 times.
Long press to start continuous measurement (don't insert the vial), then wait
for 3 to 5 minutes.
2) Open the flip cover and place the 0.0 NTU
calibration vial. Align the arrow on the vial lid with the
one on the sample vial holder and close the flip
cover.
3) Press to enter the calibration menu, the
cursor is at 0 NTU. Press to start calibration.
4) After calibration is done, press to confirm.
The instrument will return to the calibration menu
(see Diagram on the right side). The OK sign
indicates that 0 NTU has been calibrated and
prompt to calibrate 20 NTU.
5) Place the 20.0 NTU calibration vial in the sample
vial holder, press to start 20 NTU calibration.
After calibration is done, press to confirm.
The instrument will return to the calibration menu
(see diagram on the right side). The OK sign
indicates that 20 NTU has been calibrated.